With trading screens turning red after poor Chinese factory data and worries about the US Federal Reserve ending its bond buying programme, Arm is currently the biggest faller in the leading index.

The chipmaker has been under pressure since an investor day on Tuesday, with analysts concerned about increased competition from Intel in the tablet and smartphone markets. Many believe a move by Arm into the server sector may not be enough to make up for any loss of market share elsewhere.

So after losing more than 4% since the update, Arm shares are down another 6% to 986.5p as Exane BNP Paribas moved from outperform to neutral.

GKN, which also gave a presentation to analysts and investors on Tuesday, is also under the cosh, down 12.4p at 299.5p.

So Anglo American has fallen 75p to 1578.5p while Vedanta Resources is 59p lower at £12.76. Rio Tinto has lost 115p to 2927.5p and BHP Billiton has dropped 70p to £19.31.

Overall the FTSE 100 is now down 128.19 points at 6712.08, with United Utilities the only rise. The water company is up 7p at 788.5p after it said it would raise its final dividend by 7.2% despite a 9.3% fall in full year profits, due to a decrease in deferred taxation credit.

Peter Atherton at Liberum Capital said the numbers were in line with market expectations:

Underlying operating profit came in at £607m, underlying PBT came in at £354m – both broadly in line with consensus. [It remains] on track or ahead of schedule in meeting its 5-year regulatory outperformance targets.

Still with dividends, Halfords has slumped nearly 11% to 352.9p after it revealed a plan to cut its payments to shareholders to help fund a three-year turnaround plan. It is cutting its final dividend by 35% to 9.1p taking the total to 17.1p. It plans to rebase the payment to around 14p a share over the medium term.

Chief executive Matt Davies said he would invest £100m to improve its stores and online business, train staff and introduce new cycle ranges. Profits for the year fell from £92.2m to £72m. Analyst Nick Bubb said:

The new Halfords three-year plan of chief executive Matt Davies has the catchy title of "Getting into Gear 2016", but an alternative title might have been "The Duke of York Approach" ("march profits down to the bottom of the cycle and then march them up again") and it will be interesting to hear how shareholders react to the news that profits will fall further this year, will be no higher in 2016 than they were in 2012/13 and that the dividend has been "rebased", ie cut...